Test Code CDSP Celiac Disease Serology Cascade, Serum
Reporting Name
Celiac Disease Serology CascadeUseful For
Evaluating patients suspected of having celiac disease, including patients with compatible symptoms, patients with atypical symptoms, and individuals at increased risk (family history, previous diagnosis with associated disease, positivity for HLA-DQ2 and/or DQ8)
Profile Information
Test ID | Reporting Name | Available Separately | Always Performed |
---|---|---|---|
IGA | Immunoglobulin A (IgA), S | Yes | Yes |
CDSP1 | Celiac Disease Interpretation | No | Yes |
Reflex Tests
Test ID | Reporting Name | Available Separately | Always Performed |
---|---|---|---|
EMA | Endomysial Abs, S (IgA) | Yes | No |
DAGL | Gliadin(Deamidated) Ab, IgA, S | Yes | No |
TTGG | Tissue Transglutaminase Ab, IgG, S | Yes | No |
DGGL | Gliadin(Deamidated) Ab, IgG, S | Yes | No |
TTGA | Tissue Transglutaminase Ab, IgA, S | Yes | No |
Testing Algorithm
If the IgA result is within the age-specified normal range, then tissue transglutaminase (tTG) IgA antibody testing will be performed at an additional charge.
If the tTG IgA antibody result is equivocal, then endomysial IgA and deamidated gliadin IgA antibody testing will be performed at an additional charge.
If the IgA result is greater or equal to 1.0 mg/dL but lower than the age-specified normal range, then tTG IgA, tTG IgG, deamidated gliadin IgA, and deamidated gliadin IgG antibody testing will be performed at an additional charge.
If the IgA result is below the limit of detection (<1.0 mg/dL), then tTG IgG and deamidated gliadin IgG antibody testing will be performed at an additional charge.
The following algorithms are available:
Performing Laboratory
Mayo Clinic Laboratories in RochesterSpecimen Type
SerumOrdering Guidance
This cascade should not be used in patients who have previously been or are currently being treated with a gluten-free diet. For these individuals, order CDGF / Celiac Disease Gluten-Free Cascade, Serum and Whole Blood.
This cascade should not be used in individual who are negative for HLA-DQ2 or DQ8, as a diagnosis of celiac disease is unlikely. For individuals who are positive for either HLA-DQ2 and/or DQ8, this test may be ordered to assess for the presence of autoantibodies associated with celiac disease.
Cascade testing is recommended for celiac disease. Cascade testing ensures that testing proceeds in an algorithmic fashion. The following cascades are available, select the appropriate one for your specific patient situation.
-CDCOM / Celiac Disease Comprehensive Cascade, Serum and Whole Blood: Complete testing including HLA DQ
-CDSP / Celiac Disease Serology Cascade, Serum: Complete serology testing excluding HLA DQ
-CDGF / Celiac Disease Gluten-Free Cascade, Serum and Whole Blood: For patients already adhering to a gluten-free diet
To order individual tests, see Celiac Disease Diagnostic Testing Algorithm
Specimen Required
Collection Container/Tube:
Preferred: Serum gel
Acceptable: Red top
Submission Container/Tube: Plastic vial
Specimen Volume: 5 mL
Collection Instructions: Centrifuge and aliquot serum into a plastic vial.
Specimen Minimum Volume
2 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Refrigerated (preferred) | 14 days | |
Frozen | 21 days |
Special Instructions
Reference Values
Immunoglobulin A (IgA)
0-<5 months: 7-37 mg/dL
5-<9 months: 16-50 mg/dL
9-<15 months: 27-66 mg/dL
15-<24 months: 36-79 mg/dL
2-3 years: 27-246 mg/dL
4-6 years: 29-256 mg/dL
7-9 years: 34-274 mg/dL
10-14 years: 42-295 mg/dL
13-15 years: 52-319 mg/dL
16-17 years: 60-337 mg/dL
≥18 years: 61-356 mg/dL
Test Classification
See Individual Test IDsCPT Code Information
82784
86258 (if appropriate)
86364 (if appropriate)
86231 (if appropriate)
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
CDSP | Celiac Disease Serology Cascade | 94494-2 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
IGA | Immunoglobulin A (IgA), S | 2458-8 |
28991 | Celiac Disease Interpretation | 69048-7 |
Interpretation
Immunoglobulin A:
Total IgA levels below the age-specific reference range suggest either a selective IgA deficiency or a more generalized immunodeficiency. For individuals with a low or high IgA level, additional clinical and laboratory evaluation is recommended. Some individuals may have a partial IgA deficiency in which the IgA levels are detectable but fall below the age-adjusted reference range. For these individuals, both IgA and IgG isotypes for tissue transglutaminase (tTG) and deamidated gliadin antibodies are recommended for the evaluation of celiac disease; tTG IgA, tTG IgG, deamidated gliadin IgA, and deamidated gliadin IgG antibody assays are performed in this cascade. For individuals who have selective IgA deficiency or undetectable levels of IgA, only tTG IgG and deamidated gliadin IgG antibody assays are performed.
tTG IgA/IgG Antibodies:
Individuals positive for tTG antibodies of the IgA isotype likely have celiac disease and a small intestinal biopsy is recommended. For individuals with selective IgA deficiency, testing for tTG antibodies of the IgG isotype is performed. In these individuals, a positive tTG IgG antibody result suggests a diagnosis of celiac disease. However, just as with the tTG IgA antibody, a biopsy should be performed to confirm the diagnosis. Negative tTG IgA and/or IgG antibody serology does not exclude a diagnosis of celiac disease, as antibody levels decrease over time in patients who have been following a gluten-free diet.
Deamidated Gliadin IgA/IgG Antibodies:
Positivity for deamidated gliadin antibodies of the IgA isotype is suggestive of celiac disease; small intestinal biopsy is recommended. For individuals with selective IgA deficiency, testing for deamidated gliadin antibodies of the IgG isotype is performed. In these individuals, a positive deamidated gliadin IgG antibody result suggests a diagnosis of celiac disease. However, just as with the deamidated gliadin IgA antibody, a biopsy should be performed to confirm the diagnosis. Negative deamidated gliadin IgA and/or IgG antibody serology does not exclude a diagnosis of celiac disease, as antibody levels decrease over time in patients who have been following a gluten-free diet.
Endomysial IgA Antibodies:
Positivity for endomysial antibodies (EMA) of the IgA isotype is suggestive of celiac disease, and small intestinal biopsy is recommended. For individuals with selective IgA deficiency, evaluation of EMA is not indicated. Negative EMA serology does not exclude a diagnosis of celiac disease as antibody levels decrease over time in patients who have been following a gluten-free diet.
Clinical Reference
1. Rubin JE, Crowe SE: Celiac disease. Ann Intern Med. 2020 Jan 7;172(1):ITC1-ITC16
2. Lebwohl B, Rubio-Tapia A: Epidemiology, presentation, and diagnosis of celiac disease. Gastroenterology. 2021 Jan;160(1):63-75
3. Rubio-Tapia A, Hill ID, Kelly CP, Calderwood AH, Murray JA, American College of Gastroenterology: ACG Clinical Guidelines: Diagnosis and management of celiac disease. Am J Gastroenterol. 2013 May;108(5):656-676
4. Penny HA, Raju SA, Sanders DS: Progress in the serology-based diagnosis and management of adult celiac disease. Exp Rev Gastroenterol Hepatol. 2020 Mar;14(3):147-154
Report Available
7 to 9 daysMethod Name
Nephelometry
Forms
If not ordering electronically, complete, print, and send 1 of the following forms with the specimen:
-General Request (T239)
Day(s) Performed
Profile tests: Monday through Friday; Reflex tests: Monday through Saturday